Mailer SMTP connection

When I place my mail sending in a loop

Will that establish multiple connections to the SMTP server or just one ?

Usually the actual connection creation is pretty slow, so I would love to create 1 connection, then send all the messages

Any ideas ?

        foreach ($arEmails  as $key => $Email)



                ->setFrom( $Email->from )






Transport object is created once so it should be a single connection.